Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Russia and Soviet Union - 1935, Moscow - San Francisco Flight, red surcharge 1r on 10k dark brown, small ''f'' in San Francisco variety (position 7), large part of OG (gum lost at bottom left corner), VF, Soviet Philatelic guarantee hs, V. Zagorsky certificate, C.v. $1,500, Est. $700-$800, Scott #C68b